Means for holding thread-chasing dies while grinding



Feb. 19,1929. v

, F. M. SINGER MEANS FOR HOLDING THREAD CHASING DIES WHILE GRINDINGFiled 1927 5 Sheets-Shem 1 Feb. 19, 1929. 1,703,017

F. M. SINGER MEANS FOR HOLDING THREAD CHASING DIES WHILE GRINDING FiledFe 1927 5 Sheets$heet 2 22 ll- Emir-9E... A

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Feb. 19, 1929.

F. M- SINGER MEANS FOR HOLDING THREAD CHASING DIES WHILE GRINDING File1927 5 Sheets-Sheet Patented Feb. 19, 1929.

UNITED STATES FREDERICK M. SINGER, OF RACINE, WISCONSIN.

IEAN S FOR HOLDINGTHREAD-GHASING DIES WHILE GRINDING.

Application filed February 3, 1927. Serial No. 165,665.

The invention relates to improvements in work holders and has referencemore particularly to a device for holding a complete set of threadchasing dies in such a manner that 5 all necessary grinding operationson the individual dies, may be uniformly carried out.

It is one object of the invention to provide a device of the class setforth which may be easily adjusted to dispose the dies in properrelation to a grinding wheel.

It is another aim, to provide a device which will effectively hold setsof dies of different sizes and designs and will insure that uniformgrinding of all dies of the held set, shall be effected.

A further object is to provide novel means for holding any set of diesin recesses provided for their reception.

Yet another aim is to provide unique means whereby a rotatable headwhich carries the dies to be ground, may be effectively held againstfurther rotation after 7 each turn thereof, to position a die'forgrinding.

Yet another aim is to provide a rather 2 simple and inexpensive deviceof the class set forth, yet one which will be eflicient, reliable, andin every way desirable.

l/Vith the foregoing in view, the invention resides in the novel subjectmatter hereinafter described and claimed, the description beingsupplemented by the accompanying drawings.

Fig. 1 is a perspective view of the device in operative relation with agrinding wheel and its stand, arranged to grind the usual chamfer on aset of thread chasing dies.

Fig. 2 is an elevation showing the device set in operative relation witha grinding wheel for grinding the work-engaging or advance surfaces ofthe dies.

Fig. 3 is an enlarged elevation of the dieholding device.

Fig. 4 is an end elevation partly in section as indicated by line 44:ofFigB.

Fig. 5'is a top plan view.

Fig. 6 is a vertical longitudinal section as indicated by line 6-6 ofFig. 5.

Fig. 7 isan elevation of the rotatable head upon which the dies. to beground, are secured. I

The drawings above briefly described, illustrate the preferred form ofconstruction, and while this construction will be herein specificallydescribed, it is to be understood at the outset, that within the scopeof the invention as claimed, numerous variations may be made.

Moreover, such expressions as vertical and i which said base may besecured to a well known part 11 of a stand 12, commonly used forsupporting the arbor 13 of a grinding wheel 14. By means of conventionalcon struction, controlled by cranks 15 and 16, the part 11 may be movedeither longitudinally or transversely of the arbor 13. This part 11 1scustomarily provided with a T-slot which receives the heads of the bolts10, and I prefer that the base 8 be provided with lugs 18 for receptionin said slots.

An L-shaped supporting member 19, is pivoted by a vertical bolt or thelike 20, upon the base 8, said bolt passing through the base portion ofsaid supporting member. Contacting with the vertical portion of thissupporting member, is a plate or disk 21, which is pivoted to it by abolt or the like 22. When desired adjustments have been made, the bolts10, 20 and 22 are of course tightened.

Integral with the outer side of the plate or disk 21, is a bearing 23whose axis is disposed diametrically with respect to said plate or disk.This bearing rotatably receives a shaft 24, one end of which is providedwith a cylindrical head 25 which may either be integral with it orotherwise rigidly joined thereto. The other end of the shaft 24projects'beyond the bearing 23 and is preferably reduced at 26, and onthe shaft between this reduced portion and the bearing, are a nut 27 anda lock nut 28 which are used to take up end play in the shaft. A lockingcollar 29 surrounds the reduced portion 26 and may be clamped againstthe nut 28, for rotation bodily with the shaft 24L and head 25, by meansof a nut 30. However, when this nut 30 is loosened, relative turning ofthe collar 29 and the head 25, is permitted, for a purpose to behereinafter explained.

A spring-pressed, manually releasable, locking member 31 is pivoted at32 uponthe bearing 23 and is co-operable with looking portions of thecollar 29, to lock this collar against turning. In the presentdisclosure, the locking member 31 is provided with a stud 33 and thelocking portions of the collar 29, are in the form of sockets 34, any ofwhich may receive said stud. These sockets correspond in number to thenumber of dues in any of a plurality of sets whlch can be held forgrinding by the device. Customarily, there are four dies to any set, andhence four of the sockets 34 have been shown. However, if the device isconstructed to hold sets of dies in which each set contains some othernumber of dies, there will be a corresponding number of socketsprovided. The dies to be ground are mounted upon the head 25 and whileone die is being ground, the stud 33 is in one of the sockets 34. Whenthe next die is to be ground, the locking member 31 is released and thehead 25 turned to present the next die to the grinding wheel, and whensaid die arrives at the proper, predetermined point, the stud 33 willsnap into the next recess or socket 34.

The head 25 is provided with a number of sets of recesses to accommodatedifferent sets of dies to be ground. The recesses of one set are denotedat 35, those of another at 36 and those of still others at 37, 38 and39, and in the present disclosure, each set of recesses consists of fourof the latter. However, if sets of dies are to be ground having othernumbers of dies in each set, the numberot recesses in each set, providedfor the reception of the dies, would vary accordingly. The recesses ofany set are uniform in character and are uniformly spaced about theperiphery of the head 25, and it will be seen that by effecting thenecessary turning of the collar 29 with respect to said head 25, therecesses '34 of said collar may be made to engage the stud 33 of thelocking member 31, when the dies, in the selected recesses, aresuccessively and u-niformly presented at the proper point for grinding.

The formations 4O, 41 and 42, within the recesses of the head 25, may beconsidered as loeating pins, 'gibs, keys or the like, shaped to engagecomplementary portions of the standard dies now in every day use.

A spider 43 is disposed outwardly from the outer end surface 44 of thehead 25 and is pivoted at its center to the center of this head, asdenoted at 45. The arms of this spider may move into opposed relationwith the recesses 3539 of any of the sets, and set screws 46 arethreaded through said arms, to clamp the dies D in the proper recesses.In this connection, attention may be invited to the fact that eachdie-holding recess opens through the periphery of the head 25 andthrough the end surface 44 of the latter.' Thus, when the screws 16 areloosened and the spider 43 is turned to the proper extent, the dies areexposed and may be easily re moved.

Instead of using the collar 29 and the cooperating locking member 31when performing all grinding operations, I may make use of a springmetal stop finger 47 connected by appropriate supporting means 48-49,with the member 19, said finger being engageable with the dies D andbeing sufficiently resilient to permit turning of the head, that is,when any of the dies encounters the finger upon such turning of thehead, said finger will spring outwardly until the die passes and willthen snap back to the position of Fig. at to supportthe die and hold thehead 25 against rotation, during the grinding operation.

From the foregoing, taken in connection with the accompanying drawings,it will be clear to those skilled in the art, that l have produced a newand greatly improved device, for holding thread chasing dies whileperforming the necessary grinding operations upon, them. Fig. 1illustrates the manner of using the device for grinding the usualchamfers 50 upon the dies D, and as all of said dies are held in auniform manner by the head 25, they will be uniformly presented to thegrinding wheel 14, and hence will. all have the same degree of chamferperformed by said wheel.

Fig. 2 illustrates the manner in which the advance faces 51 of the diesD are ground, by the use of a larger grinding wheel 14. These surfacesalso will be uniformly ground and it will be seen that they may beground at a single setting of the machine, which is also true whengrinding the surfaces 50.

As excellent results are obtainable from the general construction shownand described, such construction is preferably followed. However, withinthe scope of the invention as claimed, variations may of course be made.

I claim:

1. A work holder comprising a head having a plurality of spaced meansfor at one time holding all of a set of duplicate members in uniformrelation with said head, and a second plurality of spaced meansdiffering from the first named means for at another time holding all ofanother set of duplicate members in uniform relation with said head;means movably mounting said head and permitting successive presentationof said spaced holding means at a common point; and means for holdingsaid head against accidental movement when any active one of said spacedmeans is disposed at said predetermined point.

2. A work holder comprising a head having a plurality of spaced meansfor at one time holding all of a set of duplicate members in uniformrelation with said head, and a second plurality of spaced meansdiffering from the first named means for at another time holding all ofanother set of duplicate members in uniform relation with said head;means movably mounting said head and permitting successive presentationof said spaced holding rneans at a common point; a locking member havinglock-engaging portions corresponding in spacing and number to either ofsaid .pluralities of holding means, releasable means for securing saidlocking member to said head in operative relation with either of saidpluralities of holding means, and a relatively stationary lockco-operable with said locking portions of said lock-engaging member whenthe latter is secured in operative relation with either of saidpluralities of holding means.

3. A work holder comprising a support, a head mounted rotatably thereon,means spaced about the axis of said head for holding a plurality ofdifferent sets of members, one set at a time, in uniform relation withthe head, whereby upon turning of the head the held members may besuccessively and uniformly presented at a common point, a locking memberco-axial with said head and having lock-engaging portions correspondingin spacing and number to the above named holding means for a set of themembers, a second locking member movably mounted on said support forsuccessive co-action with said locking portions, and means forconnecting the head and the first named locking member for normalrotation in unison, said connecting means being releasable to permitrelative turning of the head and the first named locking member to placesaid locking portions in co-operative relation with the holding meansfor any set of members.

4. A work holder comprising a support, a shaft passing rotatablytherethrough,a head secured on one end of said shaft, means spaced aboutsaid shaft for holding a plurality of different sets of members, one setat a time, in uniform relation with the head, whereby upon turning ofthe head the held members may be successively and uniformly presented ata common point, a collar upon the end of the shaft remote from the head,means for securing the collar upon the shaft for normal rotationtherewith, and a locking member movably mounted on the aforesaidsupport, said collar having locking portions for successive engagementwith said locking members, said locking portions being equal in numberand spacing to the above named holding means for a set of the members;the aforesaid collar securing means being releasable to permit relativeturning of the aforesaid head and collar, permitting said lock- .ingportions to be set in co-operative relation with the holding means forany set of members.

5. In a work holder, a member having a set of spaced. uniform recessesto at one time receive a set of duplicate members, and at least oneadditional set of spaced uniform recesses to at another time receiveanother set of duplicate members; clamping means having clampingportions equal in number to the recesses of either of said sets, andmeans mounting said clamping means for movement of said clampingportions into opposed relation with either set of recesses to clamp themembers therein.

6. A structure as specified in claim 5; said recesses being spaced abouta common point on said members; said clamping means consisting of aspider Whose arms are provided with set screws and constitute saidclamping portions, said mounting means rotatably connecting said spiderwith said member at said common point.

In testimony whereof I have hereunto

